Figure 3.

Recombinant I₂^B drives vacuole fusion along the Sec18p-dependent pathway. (A) LMA2 (I₂^B) was purified from a recombinant E. coli strain and analyzed by high-Tris SDS/PAGE and silver-staining. (B) Vacuole fusion reactions contained LMA2 in the presence or absence of Sec18p (see Materials and Methods). (C) Vacuole fusion was assayed in the presence of Sec18p and either 80 μg of yeast cytosol or 75 ng of LMA2. Assays were performed in the absence (no addition) or presence of various inhibitors of vacuole fusion (see Materials and Methods). The ATP-only background was 0.05 units.